Electrical connector



Aug. 7, 1956 c. c. MORE 2,758,280

ELECTRICAL CONNECTOR Filed May 29. 1952 gj z ff v.

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56 l lNvENToR 6 71251027 Mm' a. ff ATTORNEY 2,758,280 Patented Aug. 7, 1956 ELECTRICAL CONNECTOR Clifton C. More, Erlton, N. J., assignor to Radio 'Corporation of America, a corporation of 'Delaware Application May 29, 1952, Serial No. 290,730

Claims. (Cl. S33-6) This invention relates to electrical connectors for making a "branch connection from a main transmission line, and particularly to an electrical connector -for making a branch connection from twin-wire transmission line.

The invention may be employed to advantage to connect a plurality of receiving units employing 'twin-Wire input lines, such as `television receivers and the like, t0

a single twin-wire transmission line, such as an antenna or like signal input source.

Transmission line branch connections of the type employed in department stores, for example, multiple Ioperation from a single antenna lead-in of television reother means, ordinarily requiring considerable equipment and also involving skilled labor for installa-tion.

Accordingly, it is an object of this invention .to provide an improved electrical connector which overcomes the above and other disadvantages.

It is another object of this invention to provide an improved electrical connector for making a branch connection of a twin-wire transmission line to another twinwire antenna transmission line which `connector is relatively simple to assemble and mount, and has no serious electrical disadvantages.

It is still another object of this invention to provide an improved transmission line tap or branch connection assembly having component parts of simple construction which are easily replaceable and economical to manufacture.

A further robject of the invention is to provide a branch connector which is simple, rugged, and easily mounted to a baseboard or lthe like.

In accordance with a preferred embodiment of this invention, there is provided a transmission line tap assembly comprising a substantially cylindrical insulating body portion having transversely slotted ends upon which caps are threadedly mounted. Two parallel spaced bores through the body portion are provided for receiving a pair -of impedance elements. Recesses or cavities are provided in the ends of the `body portion both for receiving the terminal leads of the impedances to be bent into them and for securing contact thereto in a manner to be described. A pair of flat insulating inserts on one side thereof supports a pair of spaced, parallel, short conductive bars to contact the impedance leads. Each bar is connected on the other side of the insert 4to pronged contacts. Each threaded cap has a central protuberance, which on attachment extends Ilcoward the prongs. Thus upon a twin-wire transmission line being laid across the insert and across the contact prongs, and

the cap Ibeing tightened, the protuberance presses against the line, as -a biasing means, thereby forcing the prongs into the line and into contact with the wires therein. The arrangement provides a connector assembly in which the correct connections are automatically `obtained regardless yof which connector ends the respective antenna and receiver transmission lines are secured to.

The foregoing and other objects, advantages, and novel features of the invention will be better understood from lthe following description With reference to the accompanying drawing, in which like reference numerals refer to like parts, and in which:

Fig. 1 is a view in perspective showing the use `of electrical connectors between several branch receiver lines and one main transmission line in accordance with this invention;

Fig. 2 is an exploded View showing the parts of an electrical connector in accordance with the invention;

Fig. 3 is a view in longitudinal cross-section `of the connector shown in Fig. 2;

Fig. 4 is a cross-sectional view along the line 4-4 of Fig. 3; and

Fig. 5 is a schematic diagram of the connections provided between one transmission line and two other transmiss-ion lines by connectors in accordance with this invention.

Referring particularly to Fig. 1, a plurality of branch connections from a main vtwin-wire transmission line 10 to parallel-line or twin-wire transmission lines 24, 36, and 3S are made by the similar connectors 12, 14, and 16, respectively. The connectors 12, 14, and 116 are similar, and only connector 12 will be described in detail. The connector 12 comprises a body portion 18, preferably substantially cylindrical in shape, provided with transverse slots 20, 22 in the opposite ends thereof. The slot 20 receives the main transmission line 10 which may be, for example, a lead-in from a television antenna (not shown). The slot 22 receives transmission line 24, which may lead to a television receiver (not shown). End caps 26 and 28 secure Ithe respective lines f10 and 24 in place at the respective ends of the body portion 18. Through one of the caps, for example the cap 26 securing the signal conveying line 10 Within the slot 20, a screw 32 may be inserted for the purpose 4of securely attaching the connector 12 to a suitable support, such as a baseboard 34 or lthe like. The shank of the screw serves as an arbor or axle upon which end cap 26 may turn in securing line 10 to connector 12 Without twisting the line. -ln like manner, the connectors =14 and 16, similar to the connector 12 are adapted to connect respective output lines 36, 38 to the signal conveying line 10, and for -attachment to baseboard 64.

Obviously other connectors could ibe added to the signal conveying line 10 in the same manner at any desired point along line 10 without interruption of service to Ithose already connected, and without cutting, splicing, or soldering. The respective lengths of the signal conveying line 10 between the respective connectors l12, 14, 16 in actual practice may be much greater than appears in the drawing, for example of the order of. several or many feet, and these lengths may be selected at will.

Referring particularly to Figs. 2 to 4, inclusive, which show the construction and arrangement of the various parts of the connector 12, the ends of the body portion 18 are preferably identical and symmetrical to a central plane transverse to the cylindrical bodys axis. Accordingly, reference to the construction of the body portion 18, particularly at the ends thereof, will be made particularly to the upper end thereof as viewed in Figs. 2 and 3. A cavity or recess 42 is provided in the one end of the body portion 18. This recess 42 is substantially rectangular, cen? different lines, one of said caps being providedwith a central opening, and a mounting element located in said central opening, said mounting element having a shank and a head, the shank serving as an arbor for the cap only, whereby the connector may be readily mounted leaving the said one cap free for rotational engagement or disengagement with the body portion, without rotation of said body portion.

2. A transmission line tap for resistively coupling one insulated twin-wire transmission line to another insulated twin-wire transmission line comprising, in combination, a substantially cylindrical insulating body portion having an axis and having coaxial externally threaded end portions, substantially rectangular and identical recesses provided in said end portions, said body portion having a pair of bores parallel to said axis extending through said body portion between said recesses, a removable irnpedance element in each of said bores, terminal leads at the opposite ends of the impedance elements extending into the respective recesses, said leads Within each recess being arranged therein parallel to each other, normal to said axis and extending from the ends of the respective impedances to remote recessive corners of the recesses, a pair of flat insulating insert members each bearing a pair of parallel conductive bars exposed on one surface thereof, each insert resting within a different recess with the pair of conductive bars on opposite sides of said axis, whereby each conductive bar contacts with one and only one terminal lead of an impedance element, each of said conductive bars terminating in double pronged contacts extending through to the other surface of said insulating inserts, and bent at the ends to retain the bars on the flat members but with the prongs normal to said other surface, a transverse slot in each end portion of the width of twin-wire transmission line to be received therein, each said slot being also transverse to the recess at its end, two internally threaded cap portions for threaded engagement with either end of said body portion, and internal protuberances provided in said cap portions as biasing means for effecting a desired pressure of the transmission lines against said prongs to eect contact of the prongs by penetration of the twin-wire lead insulation.

3. The combination dened in claim 2, in which at least one of said cap portions is provided with a central opening extending through the protuberance thereof for receiving a screw member the shank of which may thereby serve as an arbor for the cap having the opening, and whereby the tap can be mounted in a desired manner with such screw member and connected to a main transmission line without the latter being cut, spliced, or service-disrupted.

4. A connector comprising, in combination, an insulating body portion formed with recesses in the respective opposite ends thereof for receiving the respective body portions of two insulated multiconductor cables, and with a plurality of apertures therethrough equal in number to the number of conductors in one of said cables and extending from one of said ends to the other of said ends; a contact member located in each of said recesses, respectively, each said member including an insulator plate and a plurality of pointed, outwardlyextending, conductive terminal members mounted on said plate for engaging diierent ones of said conductors; and a pair of end caps adapted to engage the respective ends of said insulating body portion and, when said cables are in place in said recesses between said contact plates and end caps, to force said cables against said pointed terminals thereby causing said terminals to pierce the insulation of said conductors and to contact different ones ot` said conductors, said apertures in said insulating body portion being adapted to receive therein coupling elements for connecting the terminals of one of said contact members to the corresponding terminals of the other of said contact members.

5.`A connector comprising, in combination, an insulating body portion formed with recesses in the respective opposite ends thereof for receiving the respective body portions of'two insulated, twin wire transmission lines, and with two apertures therethrough extending from one of said ends to the other of said ends; a contact member located in each of said recesses, respectively, each said member including an insulator plate and at least two pointed, outwardly-extending conductive terminal members mounted on said plate for respectively engaging the twin wires of said transmission lines; and a pair of end caps adapted to engage the respective ends of said insulating body portion and, when said transmission lines are in place in said recesses between said contact plates and said end caps, to force said transmission lines against said pointed terminals thereby causing said terminals to pierce the insulation lofisaid wires and to respectively contact said twin wires, said apertures in said body portion being adapted to receive therein coupling elements for connecting the terminals of one of said contact members to the corresponding terminals of the other of Said contact members.

6. A connector comprising, in combination, an insulating body portion formed with recesses in the respective opposite ends thereof for receiving the respective body portions of two insulated multiconductor cables, and with a plurality of apertures therethrough equal in number to the number of conductors in one of said cables extending from one of said ends to the other of said ends; a contact member located in each of said re-' cesses, respectively, each said member including an insulator plate and a plurality of pointed, outwardly-extending, conductive -terminal members, at least one for each conductor of one of said cables, mounted on said plate for respectively engaging said conductors of said cable; and a pair of end caps adapted to engage the respective ends of said insulating body portion and, when said cables are in place in said recesses between said contact plates and end caps, to force said cables against said pointed terminals thereby causing said terminals to pierce the insulation of said conductors and to contact different ones of said conductors, said apertures in said body portion being adapted to receive therein coupling elements for connecting the terminals of one of said contact members to the corresponding terminals of the other of said contact members.

7. A connector as set forth in claim 6, wherein said opposite ends of said body portion are provided with threads and said pair of end caps are provided with threads which are engageable with the respective threads on said opposite ends of said body portion.

8. A connector as set forth in claim 7, and further including a resistor element located in each of said apertures respectively, for connecting the terminals on one of said contact members to the corresponding terminals on the other of said Contact members, said resistor elements serving as isolating elements.

9. A connector as set forth in claim 7, wherein one of said end caps is formed with a central aperture therethrough, and further including a mounting element located in said central aperture, said mounting element serving as an arbor for said cap, whereby said connector may be mounted on a support by securing said mounting element to said support, engaging the threads of said end cap with the threads on one end of said insulating body portion, and tightening said connector by rotating said end cap about said mounting element while maintaining said body portion stationary.

10. A connector for coupling one insulated twin wire transmission line to another insulated twin Wire transmission line comprising, in combination, a substantially cylindrical insulating body portion having an axis and having coaxial, externally threaded end portions, said body portion being formed with substantially rectangular identical recesses in said end portions, said body portion having a pair of bores parallel to said axis extendingV through sa`id`bo`d$l portion between said`recesses,said

bores Being adaptedto receivetherein coupling,elements;l a p'a'ir of at' insulating insert' members, each. bearing tact a coupling element, each of saidconductive bars` terminatingiii' double pronged contacts extending through to' the other surface of saidv insulating insert memlers, andlb'ent at the ends to retain the Bars on the insulating members but with' said pronged contacts normal to said other'surface; and t'wo internally threaded cap portions forV threaded engagement with either end ofsaid' Body portions, said capportons being formed with internal projectionsgwhereby when said transmission lines are in 8 position betweeny said double pronged contactsI and-said; projections ons'aid end caps tightening said end: capsv ont'o said hod'y portionc'auses said( transmissionlinesY tol be `forged:against said contacts and'. said contacts to pierce the insulation of'said' transmission-lines and' to engagev the respective twi'n wires thereof.

Referencest (fittedin the file of this patenti UNITED STATES PATNTS" 153111533137' 

